1. Field
The following description relates to a method for making a test equipment and a test specimen for evaluating the safety of a piping, for example, to a method for making a test equipment capable of evaluating the safety of a piping and a test specimen to be used in the test equipment.
2. Description of Related Art
When designing a nuclear power plant, in order to prevent 2nd and 3rd serial break after a double ended guiliotine break (DEGB) of a high energy pipeline, massive protective walls, pipe restraints, and fluid jet preventing walls are built, and the costs for such safety designing accounts for 30% of the total designing costs.
However, when a leakage occurs before a double ended guiliotine breack (DEGB) occurs, and thus stops operation of the nuclear power plant, it is possible to save additional costs. This is called the “Leakage Before Break (LBB) Designing”. Especially, applying the “Leakage Before Break (LBB) Designing” concept when constructing a nuclear power plant is known to have hundreds of billions of economic profits per unit of power plant.
However, what is essential in applying the “Leakage Before Break (LBB) Designing” concept is the J-R Curve regarding the subject piping, which until now was calculated using a compact tension specimen (CT specimen) of a thickness of 1 inch (25.4 cm).
FIG. 1 illustrates an example of a conventional test specimen for evaluating safety of a piping.
However, conventional test specimens 10a, 10b, 10c illustrated in FIG. 1 show different J-R Curves depending on their sizes, and these J-R Curves are known to be different from the J-R Curves of real scale piping, and thus there is a problem that safety evaluation using conventional test specimen lacks reliability.
Furthermore, in some cases, an actual piping is used in conducting a J-R Curve test in order to obtain reliability in safety evaluation tests, but this costs too much and the test is more difficult.